ABSTRACT
One way to describe quantitative data is to prepare a frequency distribution. It is easier to see the shape of a distribution if the data in a frequency distribution are used to construct a figure called a frequency polygon. A frequency polygon provides a better visual summary of the data, helping researchers see the distribution of data. The smooth, bell-shaped curve has a special name: the normal curve. A researcher would get a negative skew, for instance, from administering a test of basic math skills to a large sample of college seniors. While there are other shapes, the figures shown here present the most common distributions. Whether a distribution is normal or skewed affects how quantitative data at the interval and ratio levels are analyzed. To make the proper associations with the names positive skew and negative skew, consider a number line on which zero is in the middle.
